Okay I did some research on the web on diamonds. I could only find "good" not outstanding. A good grade "D" which is the best color - true color/clear at 3.01 carats was $57,690.86. So basing it on this diamond which is good not outstanding and the price does go up for the size of the diamond. I came up with your needing 2508.36 carats worth of diamonds. Now a carat is 1/5 of a gram and a gram is .035 ounces. So for $50 million in cut good quality not outstanding you would need a little over a pound. So for outstanding diamonds it would be less. Now if it was for one of the colored diamonds I couldn't find prices on that so don't know. Hope this helps.
PS some of what determines a diamonds worth is carat, clarity, color, cut.
